Cartridge retention mechanism for a removable cartridge drive

ABSTRACT

An apparatus for retaining a cartridge in a removable media disk drive during drive operation is disclosed. The apparatus has a protuberance at a distal end of a flexible arm. When a cartridge is pushed into the drive, it engages the protuberance and flexes it along the edge of the cartridge. The protuberance flexes back when it engages a cut-out in the side of the cartridge. An opening in a side wall of the disk drive chassis allows the flexible arm to flex out when the cartridge engages it. The flexible arm is attached to a sliding lever. As the cartridge is inserted further into the drive, the flexible arm moves past the opening and thereby locks the cartridge into the drive.

BACKGROUND OF THE INVENTION

This invention relates to cartridge based data storage systems. Moreparticularly, the invention relates to the retention of a disk cartridgein a disk drive during the operation of the drive.

Cartridge based tape and disk data storage devices for storing digitalelectronic information have been in use in the computer industry forseveral decades. Removable disk cartridges typically comprise an outercasing or shell that houses a disk-shaped magnetic, magneto-optical oroptical storage medium upon which information can be stored. Thecartridge shell often comprises upper and lower halves that are formedof injection molded plastic and are joined together to house the disk.Magnetic disk media can be either rigid or flexible and are mounted on ahub that rotates freely within the cartridge. When the cartridge isinserted into a disk drive, a spindle motor in the drive engages thedisk hub in order to rotate the disk within the cartridge at a givenspeed. The outer shell of the cartridge typically has a media accessopening proximate one edge to provide the recording heads of the drivewith access to the disk. A shutter or door mechanism is provided tocover the head access opening when the cartridge is not in use toprevent dust or other contaminants from entering the cartridge andsettling on the recording surface of the disk. The shutter is commonlybiased to a closed position with a spring bias. To open the shutter andgain access to the media, the drive employs a mechanism that overcomesthe bias of the spring.

Disk drives for use with such removable disk cartridges typically employeither a linear actuator mechanism or a radial arm actuator mechanismfor positioning the read/write head(s) of the disk drive on therecording surface(s) of the storage medium, or disk. Because the diskcartridges are designed to be removable from the drive, the linear orradial arm actuators must be able to move off, and away from, thestorage medium to a retracted position in order to prevent damage to thehead(s) when a cartridge is inserted and removed from the disk drive.Moreover, many removable cartridge disk drives employ a pair of opposingread/write heads for recording and reproducing information on both sidesof a storage medium. Typically, the opposing heads are disposed onflexible suspension arms at the distal end of an actuator that allow theheads to fly closely over the respective surfaces of the rotating disk.

Disk drive also require a mechanism for allowing the heads to load onlyafter a cartridge is inserted into the drive. The actuator that carriesthe recording heads of the disk drive across the recording surfaces ofthe disk should not be allowed to move unless a disk cartridge ispresent. In the prior art, mechanical or electrical switches aretypically employed to determine the presence of a disk cartridge withinthe drive. Such switches are typically positioned so that when a diskcartridge is inserted fully into the drive, the cartridge contacts theswitch, thereby providing an indication that the disk cartridge ispresent.

When a user has completed the use of a disk cartridge, a mechanism mustbe provided to eject the disk cartridge from the drive and substantiallysimultaneously ensure that the read/write heads are retracted from thedisk into a predetermined safe position so as to prevent any damage tothe read/write heads. Typically, a tray or spring loaded lever is usedto push the cartridge out of the drive. The spring loaded tray or leveris often coupled to the head protection mechanism so that the headsprotection occurs in unison with cartridge ejection. However, where itis desirable to make the disk drive as small as possible, the mechanismsfor ejecting a disk cartridge and the linkage to the head retractionrequires additional disk drive space. The result is a drive that islarger than desirable.

Therefore, there is a need for a compact disk insertion and ejectionmechanism that overcomes the drawbacks of the prior art.

SUMMARY OF THE INVENTION

The present invention is directed to a data storage device of the typethat accepts a removable cartridge such as a removable cartridge diskdrive. The data storage device comprises a chassis and a sliding leverthat is slidably coupled to the chassis and adapted to engage theremovable cartridge and slide with the cartridge between an first(insertion) and a second (ejection) position. A flexible arm, having ancartridge holding means coupled to a distal end thereof, is coupled tothe sliding lever. The flexible arm is adapted to flex away from thecartridge when engaged by the cartridge when said sliding lever is inthe first position. The flexible arm is adapted to flex toward thecartridge such that the cartridge holding means couples the flexible armwith the cartridge when the cartridge is inserted a predetermineddistance into the storage device.

The drive also has a mechanism for preventing the flexible arm fromflexing away from the cartridge when the sliding lever is in the secondposition. This lock the flexible arm to the cartridge and prevents thecartridge from sliding out of engagement with the drive during driveoperation. The preferred mechanism for preventing the flexible arm fromflexing comprises a wall portion of the chassis extending up from thechassis proximate the second position. Thus, if the flexible arm flexesoutward, the chassis wall constrains its movement.

The cartridge holding means comprises a protuberance and cut-out pair.The protuberance could be coupled to either one of the cartridge or theflexible arm. The corresponding cut-out would then be cut into the otherone of the cartridge or the flexible arm. Preferably, the protuberanceis attached to the distal end of the flexible arm and the cut-out isformed in the cartridge. The protuberance could comprise one of manyshapes. Preferably, the protuberance comprises a cammed face.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing summary, as well as the following detailed description ofthe preferred embodiments, is better understood when read in conjunctionwith the appended drawings. For the purpose of illustrating theinvention, there is shown in the drawings an embodiment that ispresently preferred, it being understood, however, that the invention isnot limited to the specific methods and instrumentalities disclosed. Inthe drawings:

FIG. 1 is a top plan view of a disk drive according to the presentinvention;

FIG. 2A is a top view of an exemplary cartridge for use with the presentinvention;

FIG. 2B is a bottom view of an exemplary cartridge for use with thepresent invention;

FIGS. 3A shows the cartridge of FIGS. 2 in an eject/pre-insertionposition in relation to the drive of the present invention;

FIGS. 3B shows the cartridge of FIGS. 2 in a pre-eject/loaded positionin relation to the drive of the present invention;

FIGS. 4A and 4B show the operation of the cartridge retention mechanismin accordance with the present invention;

FIGS. 5A and 5B show the operation of the load eject lever inconjunction with the gear and pinion mechanism of the present invention;and

FIG. 5C shows an isometric view of pinion and sliding lever engagement.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

The present invention provides a removable media type of disk drive anda corresponding exemplary cartridge. Throughout the description, apreferred embodiment of the invention is described in connection withexemplary components. For example, a disk cartridge is shown withparticular dimensions and shape, and the drive is shown having a rotaryactuator. However, the particular disk drive and cartridge shown areprovided only to illustrate the operation of the present invention.Accordingly, the invention should not be limited to the particularcartridge or drive embodiment shown as the invention can be employedwith other cartridge and drive types and configurations.

FIG. 1 is a top view of a disk drive 50 with its top cover removed andthe components moved from there relative operational positions forclarity. Drive 50 comprises a chassis 57, an actuator 49 (preferably arotary actuator), including an opposing pair of load beams 44 having aread/write head 46 disposed at the end of each load beam, a spindlemotor 52 and a spindle 40, a load ramp 47, a shutter opening arm 48, anda load/eject mechanism which includes pinion 36, gear 24, sliding lever22, and lever compression spring 23. The operation of the load ejectmechanism is described more fully below. A disk cartridge can beinserted into the front of the drive in the direction indicated by thearrow. During insertion, the cartridge slides linearly along the topsurface of chassis 57 and spindle motor 52 for engagement with theread/write heads 46. A system for disk cartridge hub engagement with thedrive is described more fully in co-pending U.S. patent application Ser.No. 08/920932 entitled "MEDIA HUB MOUNTING SYSTEM FOR MINIMIZING Z-AXISTRANSLATION" filed Aug. 29, 1997, which is hereby incorporated byreference in its entirety.

FIGS. 2A and 2B present top and bottom views of an exemplary diskcartridge 10 for use with the drive 50 of the present invention. Diskcartridge 10 comprises a flexible magnetic disk 14, a disk media hub 12,top and bottom cartridge shell halves 18a and 18b, a rotary shutter 16,and a shutter pivot pin 20. Shutter 16 rotates within cartridge 10between an open position and a closed position. In the open position,shutter 16 is rotated away from a generally wedge shaped disk accessopening 13 that is formed in cartridge shell 18, exposing the top andbottom surfaces of disk 14 for access by a read/write head or headscontained within a disk drive. In the closed position, shutter 16 isrotated over disk access opening 13, sealing disk cartridge 10 andprotecting disk 14. The flexible magnetic disk 14 is formed of a thinpolymer film, such as MYLAR, and has a thin magnetic layer uniformlydispersed on the top and bottom surfaces. The magnetic surfacesmagnetically sensitize the flexible disk 14 and enable the storage ofdigital data when the surface is brought into magnetic communicationwith a magnetic transducer of the type commonly found in disk drives.Disk 14 is generally circular with a circular hole proximate the centerof disk 14.

Media hub 12 is firmly secured to disk 14 such that the center of hub 12is aligned proximate the center of disk 14. Media hub 12 is preferablyattached to disk 14 via a well-known adhesive process. The disk and hubassembly are rotatably disposed between upper and lower cartridge shellhalves 18a, 18b. Lower cartridge shell half 18b has a substantiallycircular spindle access opening 18c such that a disk drive can providerotational power to disk 14 via hub 12. Preferably, said access openingpresents a rounded edge.

Cartridge shell 18 also comprises a side cut-out 34 and abutment surface35. As explained more fully below, cut-out 34 and abutment surface 35engage sliding lever 22 during cartridge insertion and ejection. Cut-out34 functions to retain the cartridge in drive 50 and ensure propercartridge insertion while abutment surface 35 provides a flat surfacefor engagement and spring loading of sliding lever 22.

Referring now to FIGS. 3A and 3B, the operation of disk drive 50 inconjunction with a cartridge 10 is illustrated. FIG. 3A shows the drivemechanisms in the positions that are assumed prior to insertion of acartridge 10, which is the same positions that are assumed afterejection of a disk cartridge. By contrast, FIG. 3B shows the positionsof the drive mechanisms when a cartridge is fully inserted and the driveis operational. Referring first to FIG. 3A, actuator 49 is retractedonto load ramps 47. Sliding lever 22 is released (i.e., biased forward).And, shutter operating arm 52 is ready to engage and rotate open ashutter 16. Shutter operating arm 52 comprises a finger 52a that isadapted to engage shutter 16 and rotate it toward the open positionduring cartridge insertion. Spring tension is supplied to shutter 16from within cartridge 10 so that shutter 16 rotates back to the closedposition during ejection of cartridge 10 from drive 50. Referring nextto FIG. 3B, the cartridge is shown in the fully inserted position indrive 50. The actuator 49 is now allowed to move its read/write heads 46across the surface of disk 14, read and writing information. Spring 23is loaded to provided an ejection force to cartridge 10 via slidinglever 22 during ejection of cartridge 10 from drive 50.

Referring also to FIGS. 4A and 4B, the operation of sliding lever 22 isfurther illustrated. Sliding lever 23 comprises a flexible arm 23 with aprotuberance 32 proximate the distal end. Flexible arm 23 comprises aflexible material that bends with the application of a sidewards force.Moreover, protuberance 32 has a shape, preferably cammed, that isadapted to engage the front corner 35 of cartridge 10 and to facilitatesidewards movement of flexible arm 23. As cartridge 10 is inserted intodrive 50, protuberance 32 engages the front corner 35 of cartridge 10.As a result, when a cartridge engages protuberance 32, it rides up ontoand slides along the side wall 35b of cartridge 10. An opening 59 in thesidewall of chassis 57 provides clearance for the flexible arm 23 toflex away from cartridge 10 as cartridge 10 slides into the drive. Whencartridge 10 is sufficiently far enough into drive 10, protuberance 32aligns with cut-out 34 in cartridge 10 proximate the position indicatedby line "A" and flexes back, engaging cut-out 34. As cartridge 10 isinserted yet further into drive 50, abutment surface 35 of cartridge 10contacts an end 22a of sliding lever 22, thereby urging sliding lever 22to slide in tandem with cartridge 10 as cartridge 10 continues intodrive 50. As cartridge 10 moves further into drive 50, sliding lever 22slides from a position proximate the line "A" to a position proximatethe line "B". At this point, flexible arm 23 has moved into chassis 57past sidewall opening 59 thereby constraining flexible arm 23 by thechassis sidewall. Because the sidewards movement of flexible arm 23 isthus constrained, cartridge 10 is locked into drive 50. Furthermore, theinsertion force on cartridge 10 and sliding lever 22 compressively loadsspring 23 (see FIG. 3B).

Referring now to FIGS. 5A and 5B in conjunction with FIGS. 3A and 3B,the operation of the load/eject mechanism of the present invention isdescribed. From a user's standpoint, a cartridge 10 is loaded intooperating position in drive 50 by pushing the cartridge 10 forward intodrive 50 and then releasing the cartridge. Cartridge 10 is ejected fromdrive 50 by again pushing cartridge 10 forward into drive 50 andreleasing. The load eject mechanism that provides this user interfacecomprises the sliding lever 22, pinion 36, and gear 24. Pinion 36comprises teeth 36a, and race 26. In addition to the details providedabove, sliding lever 22 comprises an ear 39 with a post 38 projectingdownwardly from ear 39 and into race 26 of pinion 36. Gear 24 comprisesa coil spring 21, latch 28, and teeth 24a. Teeth 24a engage teeth 36a ofpinion 36, and latch 28 provides a mechanism to lock actuator 49 in aretracted position when not in operation.

In FIG. 5A, cartridge 10 has been pushed far enough into drive 50 suchthat protuberance 32 has engaged cut-out 34 in cartridge 10. At thispoint, cartridge abutment surface 35 has engaged sliding lever 22, whichis in a position proximate the line "B". Pinion 36 is in a rotaryposition proximate the line "C" and gear 24 is in a rotary positionproximate the line "E". Post 38 of sliding lever 22 is in race 26proximate location "a". Now, as cartridge 10 is pushed further intodrive 50, it urges sliding lever 22 from a position proximate line "A"to a position proximate line "B", moving post 38 along race 26 from apoint proximate "a" to a point proximate "b". This movement causes thepost to travel along the path indicated by the dashed lines in race 26in FIG. 5B. The movement of post 38 along race 26 provides a rotationalforce to pinion 36 causing it to rotate counter-clockwise from aposition proximate line "C" to a position proximate line "D".Simultaneously, as sliding lever 22 travels further into drive 50,spring 23 is loaded. While pinion 36 rotate, teeth 36a engage teeth 24a,rotating gear 24, against the bias of spring 21, from a positionproximate line "E" to a position proximate line "F". Just as cartridge10 travels past its operating position, post 38 engages the end of thefirst leg of race 26 at point "a1", preventing further forward travel ofpost 38. Because post 38 cannot travel further forward, sliding lever 22and cartridge 10 cannot move forward, signaling the user that cartridge10 has been pushed fully into drive 50. When the user releases cartridge10, spring 23 biases post 38 to travel within race 26 from point "a1" topoint "b" where it comes to rest with cartridge 10 locked in theoperating position. Latch 28 has rotated with gear 24 away from lever 45on actuator 49 by an amount indicated by the angle between lines "E" and"F". As a result of the rotation of latch 28, actuator 49 is free tomove read/write heads 46 over the surface of disk 14.

FIG. 5C shows an isometric view of the engagement between post 38 ofsliding lever 22 and race 26 of pinion 36. Race 26 is inset into pinion36 providing a track for post 38. Post 38 projects downwardly from ear39 of sliding lever 22 into race 26. Ramp 25 in race 26 helps controlthe direction of travel of post 38 in race 26, ensuring that post 38 canonly travel around race 26 in a counter-clockwise direction.

Disk ejection is reversed from the process described above. To start theejection, a user once again push cartridge 10 forward into drive 50. Theforward movement of cartridge 10 moves sliding lever 22 into drive 50.This forward movement of lever 22 moves post 38 in race 26 from a pointproximate "b" to a point proximate "c". Simultaneously, pinion 36 isfree to rotate clock-wise with the aid of spring loaded gear 24. At thispoint, forward movement of cartridge 10 is once again constrained,indicating to the user to stop pushing on cartridge 10.

As the user stops pushing on cartridge 10, spring 23 biases slidinglever 22 from a point proximate line "B" to a point proximate line "A",as post 38 moves down race 26 from point proximate "c" to pointproximate "a". The spring force applied to sliding lever 22 alsoprovides a force to eject cartridge 10 from drive 50. Meanwhile, asspring 21 rotates gear 24 counter-clockwise, latch 28 moves actuator 49to a parked position via lever 45. The heads are parked by moving loadbeams 44 and heads 46 onto load ramp 47. The mechanism for loading andunloading heads 46 is described in further detail in co-pending U.S.patent application Ser. No. 08/920594 entitled "SCISSORING LOAD RAMPSFOR A REMOVABLE MEDIA DISK DRIVE" filed Aug. 29, 1997, which is herebyincorporated by reference in its entirety.

The above description of preferred embodiments is not intended toimpliedly limit the scope of protection of the following claims. Thus,for example, except where they are expressly so limited, the followingclaims are not limited to applications involving disk drive systems.

What is claimed is:
 1. A data storage cartridge retention system anddata storage cartridge for use in a storage device, said data cartridgeretention system comprising:a chassis, a linearly sliding lever coupledto said chassis and adapted to engage the removable cartridge and slidewith said cartridge between a first and second position; and a flexiblearm having a cartridge holding means coupled to a distal end thereof,said flexible arm being coupled to said slidable lever; and said datastorage cartridge comprising: an outer shell comprising top and bottomplanar surfaces, and front, back and two side peripheral edges, saidfront peripheral edge defining at least a partially arcuate shaped frontportion of said outer shell; a disk-shaped medium disposed within saidouter shell; a media access opening proximate the front peripheral edgeof said outer shell for permitting said storage device to access saidmedium; an indent portion defined in at least one of said two sideperipheral edges of said outer shell, said indent portion adapted forengagement with the cartridge holding means; and an abutment portiondefined along a peripheral edge of said cartridge between the sidehaving the indent portion and the arcuate front portion, said abutmentportion forming a proximately right angle with the one side peripheraledge wherein the abutment is defined, said abutment portion adapted toabut said sliding lever.
 2. The data storage cartridge retention systemas recited in claim 1 wherein said holding means comprises aprotuberance.
 3. The data storage cartridge retention system as recitedin claim 2 wherein said protuberance comprises a cammed face.
 4. Thedata storage cartridge retention system as recited in claim 1 whereinsaid indent portion is proximate a front portion of said outer shell. 5.The data storage cartridge retention system as recited in claim 1wherein said front peripheral edge comprises a substantially arcuateportion.
 6. The data storage cartridge retention system as recited inclaim 1 further comprising a shell, said shell rotatably disposed withinsaid outer shell for opening and closing over said media access openingthereby allowing selective access to said media.
 7. The data cartridgeretention system as recited in claim 1 wherein the medium comprises aflexible medium.
 8. The data cartridge retention system as recited inclaim 7 wherein the medium comprises a magnetic medium.